1. Field of the Invention (Technical Field)
The present invention relates to an apparatus temporarily attachable to vehicle tires to increase traction between the vehicle tires and the surface of a roadway or driveway. The invention is particularly useful when the driving surface is covered with ice or snow, but may also be useful in other adverse conditions, such as mud or sand.
2. Background Art
To improve traction of a vehicle on mud, snow, or ice traction devices are temporarily placed on the tread portion of the tires. Such devices utilize chains, cables, metal rods, metal plates, and even a variety of plastics have been used by the public. However, few of the devices offered to date are easy to install and remove. Most involve the use of a strap buckle, tension springs, or other means that requires the user to pull on the device in order to tighten the device about the tire. In the case of tension springs this means of application and removal is often very difficult because the user lacks the leverage to pull against the spring while crouched low to the ground. Most tension springs require considerable force to apply and remove.
Rookasin, U.S. Pat. No. 4,368,769 shows a double chain traction surface that is placed transversely across the tire tread, a steel cable that is indirectly attached to the chains, and a one-way gripping cam that locks the cable as the cable is pulled through the cam by the user. The Rookasin device does not possess a ratchet mechanism for tightening the device around the tire. The tightening function must be accomplished by the brute manual pulling, by the user, of the cable through the gripping cam.
Granryd, U.S. Pat. No. 4,402,357 is similar to the Rookasin device except that a snap buckle is used to lock the connecting strap. No levered ratchet is provided to mechanically tighten the strap, rather it must be manually pulled tight by the user. Edwards, U.S. Pat. No. 3,854,514 and Jacob et al., U.S. Pat. No. 4,334,569 are similar to Granryd, except that a more traditional strap buckle is used to secure the strap. Again, no levered ratchet is provided to assist in the actual tightening effort in either device. Bowers, U.S. Pat. No. 5,454,412 shows a tire strap that is wrapped around the tire and through the wheel, and is intended to be disposable, for one-time use only. Fundamentally, the Bowers device is a single plastic strap, much like the clamping strips used by electricians to secure a bundle of loose cables. The plastic strip is pulled through the locking cam. No levered ratchet is provided to assist in the actual tightening effort.
U.S. Pat. No. 1,489,736 to Brundage, U.S. Pat. No. 1,995,758 to Stokke et al., and U.S. Pat. No. 2,066,412 to Meckler all use a tension spring to secure the traction device about the wheel.
Broadly described, the apparatus is a single length of chain that is placed transversely across the tire tread and then secured in place by a strap that is passed through the xe2x80x9cspokesxe2x80x9d of the wheel. The device has a ratchet mechanism that tightens the strap about the wheel as the ratchet lever is cranked back and forth. The principle components are a single chain (or other traction-providing surface, such as a spiked belt) having a length longer than the breadth of the treaded portion of the tire, a holding strap, a tightening strap, and a ratchet tightening and locking mechanism. In the preferred embodiment, the device also has a protective strap or other means to protect the two securing straps from abrasion or unwanted cuts. Each end of the chain or other traction providing means is attached to one end of each securing strap, a take up ratchet is secured to the other end of the holding strap, and the remaining end of the tightening strap is fed through and secured by the ratchet mechanism.
The apparatus is attached to the tire by placing the chain against the tread, and wrapping a strap against each sidewall, passing a longer strap around the xe2x80x9cbackxe2x80x9d of the tire through the wheel, and then placing the longer strap into the ratchet take-up barrel. The take up ratchet is then cranked to tighten the straps and pull the chain snugly in place, and the ratchet is then locked. In the preferred embodiment, the device includes an auxiliary xe2x80x9cprotectivexe2x80x9d strap to prevent the wheel from cutting or damaging the main securing straps. The protective strap promotes the durability of the invention. Alternatively, the tightening strap remains continuously attached to the ratchet mechanism once fed through the ratchet barrel and a quick release link is used, much like a rock climber clip, to attach and release the tightening strap from the chain or traction means surface. This allows the user to quickly apply and release the device about the wheel without the need to feed the tightening strap through the ratchet mechanism before and after every use.
Thus, according to the invention there is provided an apparatus for improving traction of a tire attached to a wheel rim with openings therein, the apparatus comprising at least one traction-providing portion disposable transversely across at least a portion of the breadth of a tread of the tire, a strap take up ratchet, a holding strap disposable through the openings in the wheel rim and having a first end attached to the traction-providing portion and a second end attached to the take up ratchet, and a tightening strap having a first end attached to the traction-providing portion and a second end movably passed through the take up ratchet, the take up ratchet being engageable with the tightening strap. Controlled actuation of the take up ratchet incrementally shortens the length of the tightening strap between the traction-providing portion and the take up ratchet. Preferably, when the take up ratchet is actuated, the holding strap is contactable with the wheel rim, and the invention includes means, attached to the holding strap, for protecting the holding strap against abrasion by the rim. The traction-providing portion preferably comprises at least one chain. The invention preferably further comprises a releasable link connecting the tightening strap to the traction surface, and a releasable link connecting the holding strap to the traction-providing portion. The means for protecting comprises a protective strap, having a width greater than the width of the holding strap. The protective strap preferably comprises woven polyester and further comprising a nylon clip connecting the protective strap to the take up ratchet.
A primary object of the present invention is to provide an apparatus for increasing vehicular tire traction, the apparatus being simple and inexpensive to manufacture.
A primary advantage of the present invention is that it is easily and quickly installed and removed from a tire.
Another advantage of the invention is that the vehicle does not have to be moved to place the apparatus upon a tire.
Another advantage of the invention is that alternative traction surfaces can be applied depending upon different road conditions.
Another advantage of the invention is that it is durable and resists wear and breakage.
Other objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention.